Stimulation patch with passive adhesion

ABSTRACT

System and methods for adhering a patch of stimulation electrode(s) to blood vessels to stimulate a target site on the blood vessel are described. In various embodiments, the system includes an adhesion patch and at least one electrode. The adhesion patch includes a passive adhesion mechanism that may produce an adhesive force sufficiently strong to adhere the adhesion patch to the exterior of the blood vessel and to operationally position the at least one electrode for use in electrically stimulating a target site of the blood vessel. The adhesion patch may also include a release mechanism that is configured for a user to disengage the patch from the exterior of the blood vessel without significant trauma to the blood vessel. After being released, the adhesion patch may be re-adhered to a different target site of the blood vessel and stimulate the different target site.

CLAIM OF PRIORITY

This application claims the benefit of priority under 35 U.S.C. §119(e)of U.S. Provisional Patent Application Ser. No. 61/745,420, filed onDec. 21, 2012, which is herein incorporated by reference in itsentirety.

TECHNICAL FIELD

This document relates generally to medical devices, and moreparticularly, to systems, devices and methods for delivering electricalstimulation.

BACKGROUND

Neural stimulation has been proposed as a therapy to treat high bloodpressure. For example, it has been proposed that electrical stimulationcan be used to reduce blood pressure when the electrical stimulation isdirected at the baroreceptor regions to induce a baroreflex response.Baroreceptors play an important role in regulating blood pressure, andare located throughout the body, but primarily in the arch of the aortaand the carotid sinuses of the left and right internal carotid arteries.Through a negative feedback baroreflex system, the central nervoussystem can regulate the BP to maintain the blood pressure at arelatively stable level. For example, when the arterial pressure risestoo high, the baroreceptors are activated and send nerve impulses to thebrain which responds by controlling the pumping activity of the heartand blood vessel dilation to reduce the blood pressure.

The blood pressure response can fluctuate dramatically when differentareas of the baroreceptor region are stimulated. For example, the bloodpressure response at a first site within the baroreceptor region can besignificantly different than the blood pressure response at a secondsite within the baroreceptor region that is within 1 mm of the firstsite. Thus, the implantation of a baromodulation device to stimulate asmall baroreceptor region in the carotid sinus usually requiresextensive mapping of the internal carotid arteries in order to find adesirable stimulation location along the carotid artery that provides aneffective or an apparently most effective control of blood pressure.Currently, surgeons manually hold one or more electrode(s) at variouslocations along the internal carotid artery to map the baroreceptorregion. This procedure takes significant time and effort due to thedifficulty of manually positioning the electrode and maintaining steadyand consistent blood pressure. Thus, the clinical procedure is oftenunable to access a full mapping area. Moreover, the manual operation maycause trauma, or introduce mechanical activation of the baroreceptorswhich may hinder the evaluation of the blood pressure responses to theelectrical stimulation.

SUMMARY

Various embodiments described herein improve the process for mapping thebaroreceptor region. For example, some embodiments adhere a patch ofstimulation electrode(s) to an exterior of a blood vessel to stimulate atarget site on the exterior of the blood vessel. By way of example, asystem embodiment may comprise of an adhesion patch and at least oneelectrode. The adhesion patch may include a passive adhesion mechanismconfigured to produce an adhesive force sufficiently strong to adherethe adhesion patch to the exterior of the blood vessel and tooperationally position the at least one electrode for use inelectrically stimulating a target site of the blood vessel. The adhesionpatch may also be configured for a user to disengage the patch from theexterior of the blood vessel without significant trauma to the bloodvessel. The adhesion patch may be configured with a size and a shape topartially wrap around the blood vessel and be in conformity with theblood vessel. The adhesion patch may be configured with a suture areafor use by the user to suture the adhesion patch in position on theexterior of the blood vessel.

A method embodiment for stimulating a target site of an exterior of ablood vessel may include adhering an adhesion patch to a target site ofthe exterior of the blood vessel, and stimulating the target site usingthe at least one electrode. A passive adhesion mechanism on the adhesionpatch may be used to adhere the adhesion patch to the target site and tooperationally position at least one electrode to the target site. Themethod may further comprise releasing the adhesion patch from theexterior of the blood vessel without significant trauma to the bloodvessel, re-adhering the adhesion patch to a different target site of theexterior of the blood vessel, and stimulating the different target siteusing the at least one electrode.

A method embodiment for determining a desirable site of a carotid arteryfor baroreceptor stimulation may include adhering an adhesion patch to afirst site of the exterior of the carotid artery, stimulating the firstsite using the at least one electrode with one or more stimulationvector configurations, sensing a physiological parameter during thestimulation of the first site, disengaging the adhesion patch from thefirst site using a release mechanism on the adhesion patch andre-adhering the adhesion patch to a second site of the exterior of thecarotid artery, and determining a desirable stimulation site using thecomparison of the sensed physiological parameter during stimulation atthe first site and the sensed physiological parameter during stimulationat the second site.

This Summary is an overview of some of the teachings of the presentapplication and not intended to be an exclusive or exhaustive treatmentof the present subject matter. Further details about the present subjectmatter are found in the detailed description and appended claims. Otheraspects of the disclosure will be apparent to persons skilled in the artupon reading and understanding the following detailed description andviewing the drawings that form a part thereof, each of which are not tobe taken in a limiting sense. The scope of the present disclosure isdefined by the appended claims and their legal equivalents.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments are illustrated by way of example in the figures ofthe accompanying drawings. Such embodiments are demonstrative and notintended to be exhaustive or exclusive embodiments of the presentsubject matter.

FIGS. 1A-B illustrate, by way of example, an embodiment of an adhesionpatch adhered to the carotid artery.

FIG. 2 illustrates, by way of example, an embodiment of an adhesionpatch.

FIG. 3 illustrates, by way of example, an embodiment of an adhesionmechanism, such as may be incorporated into the adhesion patch of FIG.2.

FIGS. 4A-D illustrate, by way of example, an embodiment of a suction cuparray and an interface between the suction cup array and a target tissuesite.

FIGS. 5A-B illustrate, by way of example, an embodiment of the adhesionpatch with suction cups.

FIGS. 6A-B illustrate, by way of example, an embodiment of the adhesionpatch with a suction material.

FIGS. 7A-C illustrate, by way of example, an embodiment of the adhesionpatch with a release tab applied to an exterior of a blood vessel.

FIGS. 8A-B illustrate, by way of example, embodiments of the adhesionpatches with a non-adhesive boundary region.

FIGS. 9A-C illustrate, by way of example, an embodiment of the adhesionpatch with one or more wires that function as an adhesion assistivestructure and a release mechanism.

FIG. 10 illustrates, by way of example, an embodiment of a stimulationsystem.

FIG. 11 illustrates, by way of example, an embodiment of a method forstimulating a target site of an exterior of a blood vessel.

FIG. 12 illustrates, by way of example, an embodiment of a method forselecting a desirable stimulation site on the exterior of a bloodvessel.

FIG. 13 illustrates, by way of example, an embodiment of a method forselecting a desirable site of an exterior of a carotid artery forbaroreceptor stimulation.

DETAILED DESCRIPTION

The following detailed description of the present subject matter refersto the accompanying drawings which show, by way of illustration,specific aspects and embodiments in which the present subject matter maybe practiced. These embodiments are described in sufficient detail toenable those skilled in the art to practice the present subject matter.Other embodiments may be utilized and structural, logical, andelectrical changes may be made without departing from the scope of thepresent subject matter. References to “an”, “one”, or “various”embodiments in this disclosure are not necessarily to the sameembodiment, and such references contemplate more than one embodiment.The following detailed description is, therefore, not to be taken in alimiting sense, and the scope is defined only by the appended claims,along with the full scope of legal equivalents to which such claims areentitled.

Disclosed herein are systems, devices and methods for adhering a patchwith stimulation electrode(s) to an exterior of a blood vessel. Theadhesion patch may be configured to partially wrap around the bloodvessel and adhere to the exterior of the blood vessel using a passiveadhesion mechanism to operationally position the at least one electrodefor use in electrically stimulating a target site. For example, thetarget site may be a site within a baroreceptor region. The adhesionpatch may also be configured for a user to disengage the adhesion patchfrom the exterior of the blood vessel using a release mechanism, and tore-adhere the adhesion patch to a different site on the exterior of theblood vessel. Thus, for example, the adhesion patch may be used to mapmultiple sites within a baroreceptor region such as a carotid sinusbaroreceptor region. The stimulation electrode(s) may be temporarilyadhered to various sites on an exterior of a carotid artery during theprocess of baromodulation mapping to select a desirable site on theexterior of a carotid artery based on a physiologic response to thestimulation. The adhesion patch may be used to position the stimulationelectrode(s) for use to chronically stimulate the site in thebaroreceptor region. The adhesion patch may also be used to adherestimulation electrode(s) to other anatomical structures includingarteries, veins, nerve bundles, tissues, and internal organs.

FIGS. 1A-B illustrate, by way of example, an embodiment of an adhesionpatch adhered to a carotid artery. Illustrated anatomical structures inthe cervical region include a segment of the carotid artery 100, acarotid sinus 101, a common carotid artery 102, an internal carotidartery 103, and an external carotid artery 104. An adhesion patch 110 isattached to a target site of an exterior of the carotid artery. Theadhesion patch includes an adhesion mechanism (not shown) configured toproduce an adhesive force sufficiently strong to adhere the adhesionpatch 110 to an exterior of a blood vessel, such as the carotid sinus101. In some embodiments, the adhesion patch also includes a releasemechanism configured for a user to disengage the adhesion patch 110 fromthe exterior of the carotid artery without significant trauma to thecarotid artery. After being released from the exterior of the carotidartery, the adhesion patch 110 can be re-adhered to a different site onthe exterior of the carotid artery.

In the illustrated embodiment, the adhesion patch 110 is connected to alead 130 via a coupling interface 120 located on or within the adhesionpatch 110. The lead 130 is electrically connected to a stimulator 140 onone end and electrically connected to one or more electrodes (not shown)associated with the adhesion patch 110 on the other end. The stimulator140 can be configured to provide desired electrical stimulation pulsesto the one or more electrodes via the lead 130. The adhesion patch 110is configured to operationally position the one or more electrodes foruse in electrically stimulating the target site of the carotid artery.The one or more electrodes may interface with the target site of theexterior of the carotid artery. Some embodiments are designed to operatewithout a lead using wireless stimulation electrode(s). In someembodiments, the adhesion patch may be designed to adhere sensor(s) to adesired location. In some embodiments, the adhesion patch may bedesigned to adhere other therapy delivering mechanisms, such as drugpatches, to a desired location.

Although FIGS. 1A-B illustrate the attachment of the adhesion patch 110on the exterior of the carotid artery, the adhesion patch 110 can beused to adhere to other anatomical structures including interior andexterior of arteries and veins, nerve bundles, heart, skin, carotidbody, stomach and intestines, bladder, soft tissues, neural tissue,gastric tissue, and other internal organs. The electrodes associatedwith the adhesion patch 110 may be used to stimulate various targets.Examples of the stimulation targets include baroreceptors, carotid body,nerve endings, nerve trunks, nerve bundles, myocardium, smooth muscle,skeletal muscle, gastric tissue, neural tissue, bladder, or othertargets.

FIG. 2 illustrates, by way of example, an embodiment of the adhesionpatch 110. The adhesion patch 110 may be configured to be used foradhering one or more electrodes associated with the adhesion patch to atarget site of an exterior of a blood vessel, or other tissues ororgans; and the electrodes can be used to stimulate the target site ofthe blood vessel and other tissues or organs. The adhesion patch 110includes a patch base 210, an adhesion mechanism 220, an optionalrelease mechanism 230, and a stimulation mechanism 240. The patch base210 functions as a mechanical supportive structure for the adhesionpatch 110. The patch base 210 may also function as a vehicle for thefunctional structures of the adhesion mechanism 220, the optionalrelease mechanism 230, and the stimulation mechanism 240.

The patch base 210 may be made of biocompatible materials of desiredrigidity, strength, and elasticity. In some embodiments, the patch baseis made of one of materials including stainless steel, titanium alloy,polymers and other synthetic biocompatible materials. The patch base 210may be customized to desired size and shape for use in contact andstimulation of the target site of a blood vessel, or other tissues ororgans. The patch base 210 may be designed in a size and shape thatallows the patch base 210 to partially wraps around the blood vessel.The patch base 210 may also be designed in a shape resembling a cuffthat completely wraps around the blood vessel. The patch base 210 may bedesigned as more than one inter-connected base pieces, each of which isconfigured to wrap around a certain portion of a blood vessel. The patchbase 210 may also have a shape in conformity with the blood vessels. Forexample, the patch base 210 may have a concave shape with adjustableconcavity to accommodate the circumferential shape of the blood vesselor other tissues or organs. The patch base 210 may be formed in anon-uniform shape to accommodate the shape of bifurcation of a portionof the blood vessel or tissues, such as bifurcation of carotid arteries.

Some embodiments of the patch base include a suture area configured foruse by the user to suture the adhesion patch in a position on theexterior of the blood vessel. Thus, once a desired location is found, asurgeon may secure the patch in place with a suture. In someembodiments, the adhesion of the patch is sufficiently strong to remainin place without a suture at least until tissue growth secures the patchin place.

An embodiment of the adhesion mechanism 220 is configured to produce anadhesive force sufficiently strong to adhere the adhesion patch to anexterior of a blood vessel or other tissues or organs, and tooperationally position one or more electrodes for use in electricallystimulating a target site of the blood vessel. The adhesion mechanism220 may be incorporated into the patch base 210 such that the adhesionmechanism 220 is in direct contact with the target site of the bloodvessel. The adhesion mechanism 220 may be incorporated into the patchbase 210 with permanent fixation, and the adhesion mechanism 220 isengaged on at least one surface of the patch base 210. The adhesionmechanism 220 may include one or more passive adhesion cups and passiveadhesion materials. The adhesion mechanism 220 may be made ofbiocompatible materials including silicone and polymers. The adhesionmechanism 220 may also include active adhesion mechanisms. Details ofthe passive adhesion mechanism are discussed below, with reference toFIGS. 4-6 and 9.

When provided, the release mechanism 230 is configured for use todisengage the adhesion patch from the exterior of the blood vesselwithout significant trauma to the blood vessel. For example, a surgeonmay use the release mechanism to disengage the adhesion patch. Therelease mechanism 230 may be incorporated into the patch base 210 suchthat a releasing force applied to the release mechanism 230 can causedisengagement of the patch base 210 from the target site of the bloodvessel. The release mechanism 230 may be incorporated into a surface ofthe patch base 210 with permanent fixation. The release mechanism 230and the adhesion mechanism may be on the same surface on the patch base.In some embodiments, while the adhesion mechanism 220 is in directcontact with the target site of the blood vessel or tissue or organs,the release mechanism 230 located on or within the patch base 210 is notin direct contact with the target site. The release mechanism mayinclude one of a plurality of passive release mechanisms and activerelease mechanisms. Details of passive release mechanism are discussedbelow, with reference to FIGS. 7-9. When no release mechanism isprovided, the patch may be released by a user to pull the adhesion patchwith a force sufficient to overcome the adhesion force.

The stimulation mechanism 240 may include one or more electrodes on orwithin the patch base 210. The one or more electrodes are configured toprovide electrical stimulation to the target site of a blood vessel. Theone or more electrodes may be configured to be permanently fixed to thepatch base 210. In some embodiments, the one or more electrodes arelocated on a side of the patch base 210 which incorporates the adhesionmechanism 220. The adhesion mechanism 220 causes the patch base 210 tobe in tight contact with the target site of the blood vessel, therebycausing the stimulation mechanism 240 and the electrodes to be in tightcontact with the target site of a blood vessel.

FIG. 3 illustrates, by way of example, an embodiment of the adhesionmechanism 220. The illustrated adhesion mechanism 220 includes a passiveadhesion interface 310 and an adhesion assistive structure 320. Thepassive adhesion interface 310 is configured to passively adhere to theexterior of the blood vessel. The passive adhesion interface 310 mayinclude one or more suction cups 311, and other suction material 312. Insome embodiments, the one or more suction cups 311 include macro suctioncups. A cup is macro when the cup is of a size that is measurable andobservable by the naked eye. For example, a macro cup has a size greaterthan 0.5 millimeters. In some embodiments, the suction cups includemicro suction cups. A cup is micro when the cup is of a size thatrequires lens or a microscope to be clearly seen. For example, a microcup has a size less than 0.5 millimeters. In some other embodiments, thesuction material 312 may include materials with pockets 313. The suctionmaterial may be a biocompatible suction tape or suction film, and thepockets 313 on the suction material 312 may be micro pockets in the sizeof 0.0001 to 1 millimeters. The micro pockets may function as microsuction cups. By applying a push force to the passive adhesion interface310, a negative air pressure can be created inside the suction cup 311,or inside the micro pockets 313 on the suction material 312, resultingin adhesion to the target site of the blood vessel.

The adhesion assistive structure 320 may include a mechanical structureto assist the user to apply the force to the passive adhesion interface310, and to cause and maintain tight engagement of the adhesion patch tothe target site of the blood vessel. For example, some embodiments ofthe adhesion assistive structure 320 include one or more wiresintegrated into the adhesion patch. In some other embodiments, theadhesion assistive structure 320 includes a mesh or lattice structure ofthe wires. Details of adhesion assistive structure 320 are discussedbelow, with reference to FIG. 9.

FIG. 4A illustrates, by way of example, an embodiment of the suction cuparray 400. The suction cup array 400 includes one or more suction cups401. The density of the suction cup array (i.e., the number of suctioncups within a specified area) depends on the size of the suction cup dand the inter-suction cup spacing p. The size of the individual cups,the spacing between cups, and the arrangement of the cups all can befactors affecting temporary adhesive performance of the patch. FIG. 4Billustrates an interface between the suction cup array 400 and a targetsite 410. As illustrated in FIGS. 4A and 4B, the suction cups 401 on thesuction cup array 400 have the same shape and size, and are uniformlydistributed in a planer array. In some embodiments, the suction cups 401on the suction cup array 400 may have different sizes and shapes; andmay be irregularly distributed on the adhesion patch.

FIG. 4C illustrates, by way of example, an embodiment of dimensionalparameters of a suction cup with flat surface, and FIG. 4D illustrates,by way of example, an embodiment of dimensional parameters of suctioncup with concave surface, where the degree of concavity is determined bypitch 8. The shape and dimension of the suction cup are selected anddesigned to obtain desired adhesion and atraumatic performance. Varioussizes of the suction cup 401, defined by d, are contemplated for thepresent application of adhesion on the blood vessels. In someembodiments, the suction cups 401 are macroscopic cups. For example, thecup surface diameter d is in the range of 0.5-5 mm. In some embodiments,the suction cups 401 are microscopic cups. For example, the cup surfacediameter d is in the range of 100-500 μm. The suction cups may be madeof biocompatible materials including silicone, polymer, and othersynthetic materials that are soft enough to promote atraumatic adhesionbetween the adhesion patch and the target site of the blood vessel orother tissues. In some embodiments, a biocompatible conductive fluid orwet gel may be included within and between suction cups. The gel orfluid provides purely viscous or visco-elastic properties so as toimprove the adhesion between the suction cups and the tissue.

FIGS. 5A-B illustrate, by way of example, an embodiment of the adhesionpatch 500 with suction cups. The adhesion patch 500 is a specificembodiment of the adhesion patch 110 used for adhering the stimulationelectrodes to the exterior of blood vessels or other tissues or organsfor target site electrical stimulation. The adhesion patch 500 includesa patch base 510, one or more suction cups 520, and one or morestimulation electrodes 540 (two shown in FIGS. 5A-B). The patch base 510provides a supporting structure for suction mechanisms, the electrodes,and lead connections. The patch base 510 may be made of non-conductivecompliable biocompatible materials. Such material allows the patch base510 to be formed into various shapes and curvatures that are inconformity with the geometry of the target site on the exterior surfaceof the blood vessel. The patch base 510 may start out in a planar state,and is configured to be convexly shaped into curved surfaces such asveins, arteries, and nerve bundles. In some embodiments, the patch base510 is configured to be shaped in conformity with the geometry ofcarotid bifurcation at 101. In some embodiments, the patch base 510 canbe made with a shape memory material, for example, to return to a planarshape after being removed from the target area on the blood vessel ortissues.

The adhesion patch has a tissue-contacting surface 512. Thetissue-contacting surface 512 may be configured to be in contact withthe exterior of the blood vessel or other target tissue. The adhesionpatch may be configured to be in connection with a lead 130 via aninterface 120 on or within the adhesion patch. The lead 130 iselectrically coupled to a stimulator 140, which generates electricalstimulation pulses and conducts the stimulation pulses through the lead130 to the stimulation electrodes 540 on the adhesion patch.

Various number and distribution patterns of the suction cups may beprovided on the adhesion patch. In some embodiments, as illustrated inFIGS. 5A-B, the suction cups and the electrodes may all be located onthe tissue-contacting surface 512 of the adhesion patch. Also asillustrated in FIGS. 5A-B, a planer array of suction cups may bedesigned such that each stimulation electrode is surrounded by aplurality of suction cups to enhance tissue stabilization during suctionand to allow reliable electrode-tissue contact. In some embodiments, thesuction cups 520, the electrodes 540, or both the suction cups 520 andthe electrodes 540 can protrude from the tissue-contacting surface 512of the adhesion patch (as shown in FIGS. 5A-B). In some embodiments, thesuction cups 520, the electrodes 540, or both the suction cups 520 andthe electrodes 540 may recess to the same level as the tissue-contactingsurface 512 of the adhesion patch. In a specific embodiment, the suctioncups 520 have openings at the same level as the tissue-contactingsurface 512 of the adhesion patch, while the electrodes 540 protrudefrom the tissue-contacting surface 512 of the adhesion patch. Such adesign would ensure close electrode-tissue contact when the suction cupsadhere to the tissue.

FIGS. 6A-B illustrate, by way of example, an embodiment of the adhesionpatch 600 with a suction material. The adhesion patch 600 is a specificembodiment of the adhesion patch 110 used for adhering the stimulationelectrodes to the exterior of blood vessels or other tissues or organsfor target site electrical stimulation. The adhesion patch 600 includesa patch base 510, a passive suction material 620, and one or morestimulation electrodes 540 (two shown in FIGS. 6A-B). The patch base 510provides a supporting structure for the suction mechanisms and theelectrodes and lead connections.

The passive suction material 620 is configured to permanently engage inthe tissue-contacting surface 512 of the adhesion patch. The suctionmaterial 620 is configured to passively adhere to the exterior of theblood vessel. The suction material 620 may contain pockets, pores, orcraters at the surface of the adhesion patch. The pockets, pores, orcraters may be macroscopic or microscopic with regular or irregularshapes. The suction material 620 may be a suction tape or suction filmwith micro pockets. The pockets on the suction material can function asthe suction cups configured to adhere to the exterior of the bloodvessel as discussed above. The suction material with the pockets may bemade of biocompatible materials including silicone, polymer, and othersynthetic materials.

In the example as illustrated in FIGS. 6A-B, the adhesion material 620covers the entire tissue-contacting surface 512 of the adhesion patch.In some embodiments, the adhesion material 620 may be configured toengage in only a partial area on the tissue-contacting surface 512.Various shapes, patterns, and spatial relations to the electrodes 540 onthe adhesion patch are contemplated. In some embodiments, as illustratedin FIGS. 6A-B, the adhesion material 620 and the electrodes may all belocated on the tissue-contacting surface 512, and each electrode may besurrounded by adhesion material 620. In some embodiments, as illustratedin FIGS. 6A-B, the electrodes 540 may be at the same level as theadhesion material 620. In some embodiments, the electrodes 540 may bemade to protrude from the surface of the adhesion material 620. Such adesign would ensure close electrode-tissue contact when the adhesionmaterial 620 adheres to the tissue.

The adhesion patch 600 may be configured to connect to a lead 130 via aninterface 120 on or within the adhesion patch 600. The lead 130 isconnected to a stimulator 140, which generates electrical stimulationpulses and conducts the stimulation pulses through the lead 130 to thestimulation electrodes 540 on the adhesion patch.

FIG. 7A illustrates, by way of example, an embodiment of the adhesionpatch 700 with a release mechanism configured for use by the user todisengage the adhesion patch 700 from the exterior of the blood vessel.The adhesion patch 700 is a specific embodiment of the adhesion patch110. The adhesion patch 700 may include the adhesion patch 500 oradhesion patch 600 as previously discussed. Additionally, the adhesionpatch 700 may include one or more peripheral margins 712, and a releasetab 770 along at least a portion of the peripheral margin 712. FIGS.7B-C illustrate the application of the adhesion patch 110 with therelease tab 770 to the exterior of a blood vessel 780. The release tab770 constitutes a release mechanism on the adhesion patch 700, andallows for use by the user to peel off the adhesion patch 110 from theexterior of the blood vessel 780 using a surgical tool such as forceps.The release tab 770 is not configured to adhere to the exterior of theblood vessel 780, such that it can be seized by the user using thesurgical tool, and the adhesion patch 700 can be peeled off from theexterior of the blood vessel 780 (e.g., along one of the directionsshown by arrows in FIG. 7C). The release tab 770 promotes the ability toatraumatically peel off the adhesive patch from the target site. In someembodiments, the release tab 770 may also be used as the suture site forpermanently suturing the adhesion patch 700 to the target site on theblood vessel or other tissues.

FIGS. 8A-B illustrate, by way of example, embodiments of the adhesionpatches 810 and 820 with a release mechanism configured for use by theuser to disengage the adhesion patches from the exterior of the bloodvessel. The adhesion patches 810 and 820 are specific embodiments of theadhesion patch 110. Similar to the adhesion patch 500, the adhesionpatch 810 includes one or more suction cups 520 and one or morestimulation electrodes 540 (two shown in FIG. 8) on a tissue contactingsurface 512. Similar to adhesion patch 600, adhesion patch 820 includesa passive suction material 620, and one or more stimulation electrodes540 (two shown in FIG. 8) on a tissue contacting surface 512. Theadhesion patches 810 and 820 each may further include a portion of aboundary region 870. The boundary region 870 does not have suction cups520, or passive suction material 620, or other adhesion mechanisms. Theboundary region 870 is configured not to adhere to the exterior of theblood vessel or other tissues, such that it can be seized by the userusing a surgical tool such as forceps, and the adhesion patch 810 can bepeeled off from the exterior of the blood vessel or tissues.

FIG. 9A illustrates, by way of example, an embodiment of the adhesionpatch 900 with an adhesion assistive structure and a release mechanism.The adhesion patch 900 is a specific embodiment of the adhesion patch110. The adhesion patch 900 may include the adhesion patch 500 andadhesion patch 600 as previously discussed. Additionally, the adhesionpatch 900 may include one or more wires 970 (two shown in FIGS. 9A-C) onthe surface or within the adhesion patch 900. The wires 970 function asa adhesion assistive structure that are configured for assisting theuser to position the adhesion patch to the exterior of the blood vessel780. The wires 970 may be made of shape-memory material. In someembodiments, the wires 970 are made out of nickel-titanium (NiTi) alloythat can maintain the adhesion patch 900 in a pre-determined shape. Insome embodiments, the wires 970 may be made of ductile stainless steel(SS) that can be formed into a custom curvature or shape by the user.The wires 970 may also be made of materials including cobalt-chromiumalloys, Elgiloy, L-605, MP35N, and 316 LVM stainless steel. In someother embodiments, the wires are made of plastic or monofilamentpolyamide materials. In some embodiments, a plurality of wires areconfigured to form a mesh or lattice structure that functions as anadhesion assistive structure. Such structure may provide additionalrigidity to the adhesion patch.

As illustrated in FIG. 9B, the wires 970 provide a rigid shape that mayallow the adhesion patch 900 to wrap the adhesion patch 900 around theanatomical structure such as the exterior of the blood vessel 780, andkeep the adhesion mechanisms (including the suction cups 520 and passivesuction materials 620) and the electrodes in contact for betteradhesion. The wires 970 may be formed to desired shape, and cause theadhesion patch to maintain in the desired shape. In some embodiments,the wires 970 may be convexly shaped to make the adhesion patch 900maintain conformity with the blood vessel 780. In some embodiments, thewires 970 may be formed into a cuff shape, promoting contact andadhesion of the adhesion patch to the anatomical surface of interest.

The wires 970 may not only function as shaping and adhesion assistivestructure that makes the adhesion patch maintain conformity with theblood vessels, but may also be configured to function as a releasemechanism that allows for use by the user to disengage the adhesionpatch 900 from the exterior of the blood vessel 780. As illustrated inFIGS. 9A-B, the adhesion patch 900 has an edge 912, and the one or morewires 970 each includes at least one end extending to the edge 912 ofthe adhesion patch 900. As illustrated in FIG. 9C, the release mechanismmay involve pulling on the midpoint of the wires 970 (shown by thearrow) using a surgical tool such as forceps, thereby releasing theadhesion surface row by row. Such a releasing mechanism may reduce theremoval force if repositioning of the adhesion patch is desired. It alsomay help reduce the trauma associated with the releasing the adhesionpatch from the target tissue. In some embodiments, the release mechanisminvolves pulling on at least one end of the wires 970 with the surgicaltool (shown by the arrows in FIG. 9C), thereby disengaging the adhesionpatch from the exterior of the blood vessel 780.

Although the wires 970 as illustrated in FIGS. 9A-C are configured to“across” the adhesion pad, the wires 970 may be incorporated into theadhesion patch in other orientation and manners. In some embodiments,the wires are along the edges of the adhesion path. The wires may form aloop, a semicircle, or an arc of a circle along the edges of theadhesion patch to facilitate releasing of the adhesion patch by theuser.

In some embodiments, the wires used for the shaping and adhesionassistive structures and the wires for the releasing mechanism areseparate wires with different constructions. For example, the wires forshaping and adhesion assistive structure are attached to one surface of,or embedded within, the adhesion patch 900, while the wires forreleasing mechanism may be attached at the outer surface and along theedges of the adhesion patch. In some embodiments, the wires 970 may beused as sites for permanent suturing of the adhesion patch to the targetsite of the blood vessel or adjacent anatomy.

FIG. 10 illustrates, by way of example, an embodiment of the stimulationsystem 1000 providing stimulations on the adhesion patch. Theillustrated stimulation system 1000 includes a stimulation mechanism 240and a stimulator 140. The stimulation mechanism 240 includes one or morestimulation electrodes 1042 and an electrode-tissue interface 1044. Theone or more stimulation electrodes 1042 are configured to be in directcontact with the target tissue such as the exterior of the bloodvessels, and deliver electrical energy to the target tissue to stimulatethe target tissue. The electrode-tissue interface 1044 may be made ofmaterial with low contact impedance and atraumatic and biocompatibleinteraction with the target tissue. In some embodiments, the fluid orwet gel may be included on the electrode-tissue interface 1044 to reducethe tissue contact impedance, and thus to improve the efficiency ofenergy delivery to the target tissue.

The stimulator 140 generates electrical stimulation energy and controlsthe delivery of the stimulation energy to stimulation electrode 1042.The stimulator 140 may be external to the patient. In some embodiments,the stimulator may be an ambulatory stimulator including an implantableand a wearable stimulator. As illustrated in FIG. 10, the stimulator 140includes a stimulation pulse generator 1080 and a stimulation controller1050. The stimulation pulse generator 1080 is configured to generate theelectrical pulses according to the commands from the stimulationcontroller 1050, and passes the electrical pulses to the stimulationelectrodes 1042 via a channel 1090. The channel 1090 may be a wire or alead electrically coupled to the stimulation electrodes 1042. In someembodiments, the channel 1090 may be a wireless channel coupled to thestimulation electrodes, where the wireless channel includes acoustic andradio frequency channels.

The stimulation controller 1050 includes a stimulation protocol selector1060 and an optional physiologic feedback controller 1070. Thestimulation protocol selector 1060 is configured to select from aplurality of stimulation protocols, or to program a stimulation protocolaccording to user's instructions. In some embodiments, the stimulationprotocol selector 1060 is configured to allow the user to selectelectrode configuration 1061, such as selecting an anode and a cathodefrom a plurality of stimulation electrodes 1042 for bipolar stimulationof the target tissue. In other embodiments, the electrode configuration1061 includes selecting an anode or a cathode from a plurality ofstimulation electrodes 1042 for unipolar stimulation in reference to areference electrode such as a can housing in an implantable stimulator.The stimulation protocol selector 1060 may also be configured to selector program a plurality of stimulation parameters 1062 for thestimulation pulse train. Examples of the stimulation parameters 1062include stimulation amplitude (voltage or current), stimulation pulsefrequency, pulse width, on- and off-time of stimulation, duty cycle ofthe stimulation pulse train, and pulse waveform or morphology.

The physiologic feedback controller 1070 is configured to receive aphysiologic response to the stimulation, and adjust the stimulationaccording to the physiologic response and one or more criteriaassociated with the physiologic response to stimulation. The physiologicfeedback controller 1070 includes a physiologic signal receiver 1071, aphysiologic parameter analyzer 1072, and a stimulation protocol adjuster1073. The physiologic signal receiver 1071 is configured to receive aphysiologic signal from a physiologic sensor. The physiologic signal mayinclude blood pressure signal, electrocardiography signal, electrogramsignal, respiration signal, neural signal, and mechanical stretchsignal. Examples of physiologic sensor include an implantable orambulatory sensor configured to sense the physiologic response, and anexternal invasive or noninvasive physiologic monitor configured to sensethe physiologic response. The physiologic sensor may also include one ormore modalities including impedance, acceleration, pressure,temperature, mechanical strain or stress, and other signals indicativeof the changes in physiologic responses to the stimulation.

The physiologic parameter analyzer 1072 analyzes the receivedphysiologic signal to determine the degree of change in a physiologicparameter due to the stimulation. For example, the physiologic parameteranalyzer 1072 may be configured to analyze the blood pressure signalduring the stimulation of the exterior of a carotid artery by computinga change in mean arterial pressure (MAP) during stimulation from thepre-stimulation MAP level.

Stimulation protocol adjuster 1073 is configured to adjust thestimulation parameters or electrode configuration if one or morepre-determined criteria are met. For example, if the MAP change issmaller than a pre-set threshold of MAP change, the stimulation protocoladjuster 1073 automatically increases the stimulation intensity byincreasing the stimulation frequency, stimulation amplitude, pulsewidth, duty cycle, etc. In some embodiments, the stimulation protocoladjuster 1073 is configured to prompt the user to manually increase ordecrease the stimulation intensity.

FIG. 11 illustrates, by way of example, an embodiment of a method 1100for stimulating a target site of an exterior of a blood vessel. Themethod 1100 may be used with the adhesion patch 110 to stimulate anexterior of a blood vessel or other tissues or organs. The method 1100starts at 1102 with positioning an adhesion patch to a target site ofthe exterior of the blood vessel. The adhesion patch may include one ormore electrodes electrically coupled to a stimulator, such as thestimulator 140 as illustrated in FIGS. 5A-B, 6 and 10. In someembodiments, the adhesion patch may include an adhesion mechanism, asillustrated by adhesion patch 110 in FIG. 2.

At 1104, by pressing the adhesion patch against the target site, anadhesive force is produced in the adhesion mechanism. The adhesive forceis sufficiently strong to adhere the adhesion patch to the target siteof the exterior of the blood vessel, and to operationally position atleast one electrode to the target site. The adhesive force may begenerated through the passive adhesion mechanism. In some embodiments,the passive adhesion mechanism includes one or more suction cups asillustrated in FIGS. 5A-B. In other embodiments, the passive adhesionmechanism includes a suction material such as that illustrated in FIGS.6A-B, where the suction material may comprise of suction tape or suctionfilm with micro pockets, pores, or craters.

Once an adhesion patch is adhered to the target site, at 1106, thetarget site is stimulated using at least one electrode that is providedon the adhesion patch. In some embodiments, the stimulation pulses aredelivered according to a pre-determined protocol that defines thestimulation intensity and stimulation time. In some embodiments wheremore than one electrode is provided, the stimulation is deliveredaccording to a pre-determined electrode configuration that defines theanode and cathode electrodes used for stimulation. In some embodiments,the stimulation may be adjusted automatically or manually according tophysiologic response to the stimulation. For example, if thephysiological response does not meet one or more criteria, thestimulation protocol, including the stimulation electrode configurationand the stimulation protocol, may be adjusted; and new stimulationpulses can be delivered to the target site via the electrodes on theadhesion patch.

FIG. 12 illustrates, by way of example, an embodiment of a method 1200for selecting a desirable stimulation site on the exterior of a bloodvessel. At 1201 an initial site on the exterior of the blood vessel isselected for stimulation. At 1202, an adhesion patch is positioned atthe selected site. The adhesion patch, such as the adhesion patch 110,may include an adhesion mechanism, a releasing mechanism, and astimulation mechanism. To allow the adhesion patch to be securely andatraumatically attached to the target site on the exterior of the bloodvessel, the side on the adhesion patch with adhesion mechanism may bepositioned to the target stimulation site. At 1203, by pressing theadhesion patch against the target site, an adhesive force is produced inthe adhesion mechanism. The adhesive force is sufficiently strong toallow the adhesion patch to be securely adhered to the target site; andthe one or more electrodes to be in close contact with the targettissue. In some embodiments, the passive adhesion mechanism may includeone or more suction cups as illustrated in FIGS. 5A-B. In otherembodiments, the passive adhesion mechanism may include a suctionmaterial as illustrated in FIGS. 6A-B, where the suction material maycomprise of suction tape or suction film with micro pockets or pores.Then, at 1204, the target site is stimulated using at least oneelectrode that is provided on the adhesion patch. The response to thestimulation is recorded and evaluated at 1205. In some embodiments, theevaluation was performed by sensing one or more physiologic signals,analyzing a physiologic parameter computed from the sensed physiologicsignal, and determining the significance of the physiologic response tothe delivered stimulation by, for example, comparing the physiologicparameter to a pre-determined threshold. If the responses to stimulationat a plurality of sites are available, at 1206, the responses ofdifferent stimulation sites are compared to determine if the presentstimulation site is “desirable”. In some embodiments, among thestimulation sites on the exterior of a blood vessel, a desirable site isdetermined to be the tested site that, when stimulated, results in thegreatest drop in mean arterial pressure from a pre-stimulation baselinelevel. In some other embodiments, a desirable site is determined to bethe tested site that, when stimulated, results in the lowest meanarterial pressure.

If at 1206 the present stimulation site is deemed “desirable”, then at1209 the site selection process is completed, and the adhesion patch canbe sutured at the desirable site, or secured at the desirable site withtissue growth, for chronic electrical stimulation. However, if thepresent site is not deemed desirable, then at 1207, the adhesion patchis disengaged from the present stimulation site. The disengagement ofthe adhesion patch may be achieved by using the release mechanism on theadhesion patch. The release mechanism may include a release tab 770along at least a portion of the peripheral margin 712, as illustrated inFIG. 7. The release mechanism may also include at least a portion of theboundary region 870 on the adhesion patch, where the boundary region 870is configured not to adhere to the exterior of the blood vessel, asillustrated in FIG. 8. In some embodiments, the release mechanism mayinclude one or more wires 970, each of which including at least one endextending to an edge of the adhesion patch, as illustrated in FIG. 9.The release mechanism allows for use by the user to peel off theadhesion patch from the exterior of the blood vessel with no or minimaltrauma to the tissue. At 1208, a different target site may be selectedfrom the exterior of the blood vessel, and the released adhesion patchmay be re-positioned to a new site and the stimulation can be repeatedat the new site.

FIG. 13 illustrates, by way of example, an embodiment of a method 1300for selecting a desirable site of an exterior of a carotid artery forbaroreceptor stimulation. This method can be used, for example, in theprocess of baromodulation mapping before implant of a baromodulationdevice for chronic blood pressure control. By extensive and effectivemapping of the internal carotid arteries, a desirable stimulationlocation on the carotid artery can be found which provides safe and mostefficacious baroreceptor stimulation for blood pressure control.

At 1301 an initial site on the exterior of the carotid artery forstimulation is selected. Then, at 1302, an adhesion patch is positionedat the selected site on the exterior of the carotid artery. At 1303, bypressing the adhesion patch against the carotid artery, an adhesiveforce is produced in the adhesion mechanism. The produced adhesive forceis sufficiently strong to allow the adhesion patch to be securelyadhered to the target site; and the one or more electrodes to be inclose contact with the target tissue. The passive adhesion mechanism mayinclude one or more suction cups as illustrated in FIGS. 5A-B, andsuction material as illustrated in FIGS. 6A-B. The suction material maycomprise of suction tape or suction film with pockets, pores, orcraters. At 1304, the target site is stimulated using at least oneelectrode that is provided on the adhesion patch. In some embodiments,the stimulation delivered at one target site includes a plurality ofstimulation vectors and electrode configurations, a plurality ofstimulation protocols with different stimulation parameters (e.g.,stimulation intensity, frequency, pulse width, etc.), and a permutationof the stimulation electrode configurations and stimulation protocols.On the first target site of the carotid artery, stimulation pulsesaccording to the selected stimulation protocol and electrodeconfiguration are delivered, and a physiologic parameter during thestimulation is sensed at 1305. The physiologic parameter may includeblood pressure signal, electrocardiography signal, electrogram signal,respiration signal, and neural signal. The physiologic parameter may besensed using an implantable or ambulatory sensor, or an externalinvasive or noninvasive physiologic monitor that senses the physiologicresponse. In various embodiments, the sensor may include one or moremodalities including impedance, acceleration, pressure, temperature,chemical concentration and other signals indicative of the changes inphysiologic responses to the stimulation. The physiologic parameter isanalyzed to determine the degree of change in the physiologic parameterdue to the stimulation. In some embodiments, during each stimulationelectrode configuration and stimulation protocol, blood pressure signalduring the stimulation of the exterior of a carotid artery is sensed,and the change in mean arterial pressure (MAP) from the pre-stimulationMAP level is determined. The physiologic response is compared to apre-set criterion at 1306 to determine if the present site ofstimulation is the desirable site. In some embodiments, the pre-setcriterion may include a threshold value of the change of the MAP duringstimulation from a pre-stimulation baseline MAP level. In someembodiments, the pre-set criterion may include a threshold value of theMAP level during stimulation.

If at 1306 the present stimulation site was deemed desirable, then at1309, the site selection is completed, and the adhesion patch can besutured, or secured with tissue growth, at the desirable site of thecarotid artery for chronic or permanent stimulation therapy to maintaina controlled and stable blood pressure. However, if the physiologicparameter does not meet the pre-set criterion (for example, the drop inMAP during stimulation at the present site is smaller than the pre-setthreshold for the change in MAP, or the MAP during stimulation is higherthan a pre-set MAP level), then at 1307, the adhesion patch isdisengaged from the present stimulation site. The disengagement of theadhesion patch may be achieved using one or more release mechanismsprovided on the adhesion patch. The release mechanism may include arelease tab 770 along at least a portion of the peripheral margin 712 asillustrated in FIG. 7, and at least a portion of boundary region 870 onthe adhesion patch, where the boundary region 870 is configured not toadhere to the exterior of the blood vessel, as illustrated in FIG. 8. Insome embodiments, the release mechanism may include one or more wires970, each of the one or more wires including at least one end extendingto an edge of the adhesion patch, as illustrated in FIG. 9. Each ofthese embodiment of release mechanism allows for use by the user to peeloff the adhesion patch from the exterior of the blood vessel with no orminimal trauma to the tissue. Then, at 1308, a different target site maybe selected from the exterior of the carotid artery. The releasedadhesion patch can be re-positioned to the new site, and the stimulationcan be delivered to the new site.

The above detailed description is intended to be illustrative, and notrestrictive. Other embodiments will be apparent to those of ordinaryskills in the art upon reading and understanding the above description.The scope of the disclosure should, therefore, be determined withreferences to the appended claims, along with the full scope ofequivalents to which such claims are entitled.

What is claimed is:
 1. A system, comprising at least one electrode; andan adhesion patch, wherein the adhesion patch includes a passiveadhesion mechanism configured to produce an adhesive force sufficientlystrong to adhere the adhesion patch to an exterior of a blood vessel andto operationally position the at least one electrode for use inelectrically stimulating a target site of the blood vessel, and whereinthe adhesion patch is configured for a user to disengage the patch fromthe exterior of the blood vessel without significant trauma to the bloodvessel.
 2. The system of claim 1, further comprising a stimulatorconfigured to generate electrical stimulation pulses, wherein thestimulator is operationally connected to the at least one electrode tostimulate the target site of the blood vessel.
 3. The system of claim 2,wherein the at least one electrode includes an electrode pattern of morethan one electrode, and the system is configured to selectively deliverelectrical stimulation pulses using different electrodes selected fromwithin the electrode pattern.
 4. The system of claim 1, wherein thepassive adhesion mechanism includes a plurality of suction cupsconfigured to passively adhere to the exterior of the blood vessel. 5.The system of claim 1, wherein: the adhesion patch includes a surface;the passive adhesion mechanism includes a suction material, the suctionmaterial configured to passively adhere to the exterior of the bloodvessel; and the suction material containing pockets at the surface ofthe adhesion patch.
 6. The system of claim 5, wherein the pocketsinclude regular-shaped micro-pockets.
 7. The system of claim 5, whereinthe pockets include irregular-shaped micro-pockets.
 8. The system ofclaim 1, wherein the adhesion patch includes an adhesion assistivestructure configured for the user to position the adhesion patch to theexterior of the blood vessel.
 9. The system of claim 8, wherein theadhesion assistive structure includes one or more wires made ofshape-memory material.
 10. The system of claim 8, wherein the adhesionassistive structure is convexly shaped to make the adhesion patchmaintain conformity with the blood vessel.
 11. The system of claim 1,wherein the adhesion patch includes a release mechanism configured foruse by the user to disengage the adhesion patch from the exterior of theblood vessel.
 12. The system of claim 11, wherein: the adhesion patchincludes a peripheral margin; the release mechanism includes a tab alongat least a portion of the peripheral margin for use by the user to peeloff the patch from the exterior of the blood vessel; and the tab is notconfigured to adhere to the blood vessel.
 13. The system of claim 11,wherein: the adhesion patch has an edge, and the adhesion patch includesone or more wires; the one or more wires each includes at least one endextending to the edge of the adhesion patch; and the release mechanismincludes the at least one end of the wire extending to the edge of theadhesion patch for use by the user to peel off the patch from theexterior of the blood vessel.
 14. The system of claim 1, wherein theadhesion patch includes a suture area configured for use by the user tosuture the adhesion patch in position on the exterior of the bloodvessel.
 15. The system of claim 1, wherein the adhesion patch isconfigured with a size and a shape to partially wrap around the bloodvessel and be in conformity with the blood vessel.
 16. A method ofstimulating a target site of an exterior of a blood vessel, the methodcomprising: adhering an adhesion patch to the target site of theexterior of the blood vessel, wherein adhering the adhesion patchincludes using a passive adhesion mechanism on the adhesion patch tocause the adhesion patch to adhere to the target site and tooperationally position at least one electrode to the target site; andstimulating the target site using the at least one electrode.
 17. Themethod of claim 16, further comprising releasing the adhesion patch fromthe exterior of the blood vessel without significant trauma to the bloodvessel.
 18. The method of claim 17, further comprising re-adhering theadhesion patch to a different target site of the exterior of the bloodvessel, and stimulating the different target site using the at least oneelectrode.
 19. A method of determining a desirable site of an exteriorof a carotid artery for baroreceptor stimulation, the method comprising:adhering an adhesion patch to a first site of the exterior of thecarotid artery, wherein adhering the adhesion patch includes producingan adhesive force using a passive adhesion mechanism on the adhesionpatch to cause the adhesion patch to adhere to the first site and tooperationally position at least one electrode to the first site;stimulating the first site using the at least one electrode with one ormore stimulation vector configurations; sensing a physiologicalparameter during the stimulation of the first site; disengaging theadhesion patch from the first site using a release mechanism on theadhesion patch and re-adhering the adhesion patch to a second site ofthe exterior of the carotid artery; and determining a desirablestimulation site, wherein determining the desirable stimulation siteincludes comparing the sensed physiological parameter during stimulationat the first site and the sensed physiological parameter duringstimulation at the second site.
 20. The method of claim 19, wherein:producing the adhesive force using the passive adhesion mechanism on theadhesion patch includes using at least one from a group of passiveadhesion mechanisms, the group of passive adhesion mechanisms consistingof suction cups and suction material containing pockets; producing theadhesive force using the adhesion mechanism on the adhesion patchincludes placing the passive adhesion mechanism in contact with theexterior of the carotid artery; and disengaging the adhesion patchincludes using at least one from a group of release mechanisms for useby a user to peel off the adhesion patch from the carotid artery, thegroup of release mechanisms consisting of a peripheral margin of theadhesion patch and one or more wires attached to the adhesion patch,each of the one or more wires including at least one end extending to anedge of the adhesion patch.